Methyl Red Voges-Proskauer Test Lab

PURPOSE
This experiment is designed to become familiar with and perform the MR-VP biochemical test, learn variations in how different organisms metabolize glucose, and to become familiar with and perform the catalase biochemical test.

PROCEDURE
Exercise 1
Procedural Steps
The saved E. coli culture and S. epidermidis stock culture was incubated 12-24 hours prior to the start of the experiment.
The work area was disinfected with 10% bleach solution.
The MR-VP tubes were labeled: one E coli and the other S epidermidis.
Each MR-VP broth tube was inoculated with the corresponding organism using aseptic techniques.
The tubes were incubated for 48 hours at 35oC-37oC
The reagents were allowed to warm to room temperature
Two test tubes were labeled E. coli and two test tubes were labeled S. Epidermidis
Half (2.5 mL) of the incubated MR-VP broth labeled E. coli was transferred into the two corresponding test tubes. This was repeated for the broth labeled S. epidermidis.
One tube for each organism was chosen for the Methyl Red test and labeled accordingly.
Using the pipet, six to eight drops of Methyl Red reagent was added to each of the tubes. If the test was positive, the red-pink color of acid presence from glucose appeared within seconds.
The remaining two tubes were for the Voges-Proskauer test. Twelve drops of Baritt’s A…...

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[pic]
(Fractured Copper Specimen)
By: Christl Burns
Mechanics of Materials Sec. 4
Lab Preformed on: 2/9/12
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First a punch was used to mark off a two inch section on each specimen. This section was marked off so that it could be used as a reference in finding the elongation of the specimen.Then, using a caliper, the diameter of each was measured and recorded. Now the mechanist calipers were set up in increments of 0.05 inches starting at 2.05 inches. Next the specimen was loaded into the tensile testing apparatus, the extensometer was put onto the specimen, and the......

...Lab 1: Tension Test
Andrew Thiher
2/17/2012
Introduction:
In this lab, we tested the material properties of 836 cold rolled steel, T351-2024 aluminum, 110 copper, grey cast iron, and high-density polyethylene (HDPE) by subjecting each material to a tensile force until it fractured. Using data gathered, we graphed the stress-strain graph and determined specific properties for each material. These properties included whether the specimen was ductile or brittle, yield stress, and tensile strength. For equations used, see appendix 2.
Experimental Apparatus:
Each material was prepared for the experiment by marking the initial length as two inches by means of a gage punch and hammer. Additionally, calipers were used to measure the initial diameter. The sample was then screwed into the tensile testing machine and an extensometer was attached to measure elongation and collect data. The extensometer remained attached until the material reached its proportional limit, at this point it was removed, and the remaining data was collected using machinist scales prepared in .05 inch increments. Each time the gauge length reached the preset machinist scale increment, the live load from the computer was recorded. This process was repeated until the specimen fractured. Once the specimen fractured, the final gauge length and smallest diameter in the necking region were recorded.
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[pic]
|Property |Cold Steel |110...

...POINT LISAS CAMPUS
Esperanza Road,
Brechin Castle,
Couva
www.utt.edu.tt
LAB 1
Decomposition reaction
Aim: Determination of the number of moles of water molecules of crystallization present in hydrated Magnesium Sulphate (MgSO4.xH2O)
Apparatus: Mass balance, test tube, test tube holder, heat-proof mat and bunsen burner.
Reagents: Hydrated sodium carbonate.
Theory: Chemical decomposition, analysis or breakdown is the separation of a chemical compound into elements or simple compounds. A more specific type of decomposition is thermal decomposition or thermolysis, which is caused by heat. ABA+B, the reaction is endothermic, since heat is required to break the chemical bonds. Most decomposition reaction require energy either in the form of heat, light or electricity. Absorption of energy causes the breaking of the bonds present in the reacting substance which decomposes to give the product. When a hydrated salt is heated it decomposes into a pure form of the salt and water.
MgSO4.xH2O MgSO4 + H2O
Procedure:
Refer to Handout
Results:
A. Mass of test tube/g = 21.77
B. Mass of the tube and salt/g = 24.0
A table showing the mass of the test tube and salt after 3 consecutive heating:
Heating | Mass of the test tube and salt/g |
1st | 23.96 |
2nd | 23.81 |
3rd | 23.81 |
Calculations:
G. Mass of anhydrous magnesium sulphate/g = F - A = 23.81 – 21.77= 2.04
H. Mass of water of crystallization......

...Lab Write Up
Identifying an Unknown Microbe
Gregory Howard
10E
The isolation
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The Gram Stain
Next I performed a gram stain to detect differences between microbes or differences in structure of the same microbe. This being my first time I ever gram stained false results could be because of poor staining techniques. Usina a modern light microscope I observed each microbe that grew on its agar plate of interest. Through my gram staining and visual observation I came to the conclusion that the macconkey agar plate grew enterobacteriace , a GN rod shape org and the org that grew on the Columbia can plate resembled a cocci due to its......

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I. CATALASE TEST + result vigorous effervescence
II. COAGULASE TEST
III. MANNITOL SALT FERMENTATION TEST
IV.DNASE TEST
*
* Staphylococus aureus on the left is negative for DNase production; the Serratia marcescens on the right is positive for DNase production as evidenced by the area of clearing around the growth.
IV. NOVOBIOCIN TEST
Rapid, automated identification of novobiocin-resistant, coagulase-negative staphylococci. (CoNS)
ID of Staph.saprophyticus
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...purpose of microbial biochemical tests is to identify the unique traits it yields and with that knowledge we can then categorize them in groups and specify them by scientific name. These experiments included the Triple-sugar iron agar (TSIA), Sulfur Indole Motility (SIM), Methyl Red (MR), Voges-Proskauer (VP), Citrate, Urease, Gelatin, and Oxidase Test. In order for these tests to produce reliable and credible results, the bacterium organism must be grown using strict and meticulous procedure to produce viable colonies of pure culture. Having pure culture is significant to ensure that a single type of bacteria is used for identification without contamination so tests can be run without complications or confusion. Once all these tests are performed, the unknown bacteria in this lab will be one of the following: Escherichia coli, Enterobacter aerogenes, Proteus mirabilis, Klebsiella pneumoniae, or Salmonella typhimurium. This report included the results and details to these experiments which are discussed further on.
Abstract
Gram negative bacteria Unknown #12 was run through an array of tests which produced positive and negative results. The results obtained from the various tests were used for the process of elimination with the use of our Gram Negative Unknown chart to conclude that unknown #12 was Proteus mirabilis. This report will include information regarding the methods and materials used as well as the discussion about the biochemical tests and the results.......

...Systematic Methodology used in the Identification and
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By: Richard Martinez
MCB-2010L Microbiology Lab
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11/29/13
Unknown bacteria were determined to be Escherichia coli and Bacillus cereus
due to their morphological, physiological and metabolic properties.
I. Abstract
In a laboratory setting, it often becomes necessary to identify an unknown organism. In this experiment, researchers classified some unidentified bacteria based on their physical structure, colony morphology, optimal conditions and metabolic properties. A Gram stain using crystal violet, iodine, and safranin and a simple stain using methylene blue characterized the organism’s cell walls. Cultural behaviors were classified by inoculating the organisms onto nutrient agar and incubating them at 30° and 37° C for 48 hours, and observing their behaviors, as well as using Mannitol and phenol red media for fermentation and acid production. Optimal growth temperatures were determined by incubating nutrient agar plates of the organisms at 30° C and 37° C. The metabolic profile was created by inoculating the bacterium into broths containing lactose, mannitol, and citrate and incubating the tubes at 30° and 37° C for 48 hours, then observing them for color change. The stains revealed that the bacteria were both Gram-negative and Gram-positive bacilli.
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On the scale of 1 to 5, my grit test score was a 2.57, I gave every answer my time and was full honest but for some reason it just doesn’t make much sense. This test of grit is supposed to measures conscientiousness courage, excellence, resilience, and endurance versus perfection.
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A. What is meant by the term biochemical profile?
Biochemical profile is comprised of the specific pathway or molecules used in metabolic processes by an organism. This helps to identify a particular species of organism.
B. What metabolic end product does the MR test for?
Methyl Red or MR is a test used to identify bacteria based on the way they metabolize glucose.
C. What does an orange color indicate as a result for an MR test?
The orange result in an MR test, is an indicator that the test was inconclusive. It is possible that the bacteria produces some acidic products, but not enough to overwhelm the phosphate buffer in the broth to turn it red.
D. What metabolic end product does the VP test for?
The end product we are testing for in the VP test is acetoin or acetyl methyl carbinol. I tested E.coli and S. epidermidis by preparing two tubes with incubated broth of each organism and added 12 drops of Barrit’s A Reagent to each tube. After mixing gently, I added 4 drops of Barrit’s Reagent B to each tube, shook gently and allowed to stand for 30 minutes.
E. Why do you need to be careful not to jostle the VP tube while waiting for the results to show?
It is important not to move or shake the tubes because the Reagent A and B cause the acetoin to produce a maroon band that rises to the top of the broth indicating a positive VP result. If the tube was shaken it would stir the band into the broth and appear to be a......

...Synthesis of Methyl Orange
Jineui Jung
Abstract
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Introduction
Methyl orange synthesis is diazo coupling reaction between the diazonium sale of sulfanilic acid and N,N-dimethylaniline. The initial product gained through coupling reaction is red acid form of methyl orange and this later turned to orange sodium salt, called methyl orange. Dyes are used to give colors to fabrics and Chromophores, functional groups that absorb light, give color to these dyes. The most common chromophores are azo, nitro, and carbon groups.
The method of diazotiation is dependent on how basic and soluble the amine being coupled is. As sulfanilic acid is insoluble in acid, sulfanilic acid is dissolved in a basic solution. Primary aromatic amines can be directly diazotized but......

...Unknown 6: Micrococcus Luteus
Introduction:
This lab requires us to learn about cultural, morphological and biochemical characteristics that are used in identifying bacteria. These characteristics and unique aspects can be observed by learning and using the various different tests and techniques, which is the main purpose here, and can help pinpoint the identity of the unknown organism. Each student will receive a slant containing one species of bacteria. The assignment is to verify the purity of the culture, maintain a stock culture, and identify the unknown by its unique characteristics. These characteristics include: Gram (+) vs. Gram (-), motility, spore-staining, etc.
Procedure:
Materials and methods used are detailed in the BIO 2710 Microbiology Laboratory Manual.
Results:
The following is a descriptive chart of all the lab techniques/tests performed for identifying unknown 6:
Descriptive Chart: Study of an Unknown Bacterium |
Name: _Ali Ahmad__BIO2710 Winter 2015Identifying an Unknown Bacterium | Habitat : ___________ Culture # ___6______Source: __Bergey’s Manual____________Organism: _Micrococcus Luteus______ |
Morphological Characteristics | Physiological Characteristics |
Cell shape: CocciArrangement: MassesSize:---------Spores: No SporesGram’s Stain: Gram (+)Motility: NonmotileCapsules: -------Special Stain: appear blue to violet when stained using a Gram-stain technique | TESTS | RESULTS |
| FERMENTATION | Glucose |......

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Safety Analysis of a High Voltage Test Lab
by
David Wallace
for
ISE 6173
Instructor: Dr. Kari Babski-Reeves
Spring 2015
ABSTRACT
In the production of electrical transformers, dielectric test must be performed to certify the transformer will function properly in the field. These tests are conducted in a high voltage test lab (HVTL) where voltages can reach in excess of 500,000 volts. This health and safety assessment was performed on a HVTL to identify potential safety and health hazards within the lab and apply engineering controls, administrative controls and personal protective equipment to mitigate the hazard. This assessment was accomplished through the use of risk assessment, deviation analysis, job safety analysis, HAZOP and fault tree analysis following a five step method. Each hazard was quantified based on the consequence and the probability of occurring and classified based on the type of risk and the acceptance of the risk. From this analysis, the ten most critical hazards were chosen. These ten were then mitigated using the various controls listed above.
* TABLE OF CONTENTS
ABSTRACTii
INTRODUCTION1
METHODS2
2.1 Safety and Health Analysis Tools2
2.1.1 Risk Assessment Analysis2
2.1.2 Deviation Analysis3
2.1.3 Job Safety Analysis5
2.1.4 Hazard and Operability Analysis5
2.1.5 Fault Tree Analysis6
2.2 Procedures for Five-Step Analysis6
2.2.1 Risk Assessment Analysis of Building and Facility7
2.2.2 Deviation Analysis of Hazardous Substances7
2.2.3 Job Safety......

...Process and Techniques of Finding Unknown J
Abstract:
As part of a focal study within Microbiology, many scientists have endeavored to identify the many species and types of microbes found in different environments. In an effort to categorize, understand and distinguish one microbe from another, scientists developed tests to show unique characteristics of microbes. This experiment enlists these tests, such as PCR, Simple and Gram staining, anaerobic growth tests, IMViC, Catalase, Oxidase, selective and differential media to identify an unknown microorganism. The Unknown organism studied was labeled “J” and found to be a gram negative, rod shaped bacteria that does not produce endospores. The selective and differential agars produced no growth on the MSA agar plate showing that the bacteria did not favor a salty environment of the Mannitol salts and showed an acidic by product in the selective and differential media of MacConkey’s Agar. The bacteria showed to metabolize sugars but did not produce any gaseous byproducts. After 16s rRNA was processed and run through a PCR, electricphoresis was used to run the RNA out on a gel in order to sequence the RNA which was then compared in a database. Furthermore, the Unknown J did not produce or metabolize starch. The bacteria did not react with the Citrate, KEY oxidase. When compared to other known bacteria tested, unknown J proved to be Escherichia coli.
Introduction:
Identifying bacterial causes for certain diseases that have...

...Cover Glass - Cover Slip Cube (4)
Culture Media
Bag #2 -
Refrigerate
upon Receipt
Culture Media Bag #2 -
Refrigerate upon
Receipt
2 Agar, 0.4% Motility Test Agar - 8 mL in Glass
Tube
Inoculation
Instruments
Inoculation
Instruments
1 Inoculation Loop, Plastic
Mask Bag Mask Bag 1 Mask with Earloops (11) in Bag 5" x 8"
Slide Box MBK Slide Box MBK 1 Slide-Box-MBK with Blank-Slides (4)
Pre-Lab Preparation: Place saved cultures of E. coli and S. epidermidis (from previous
lab) in incubator 12-24 hours prior to the start of the experiment.
Discussion and Review: Many bacteria are capable of
motility, the ability to move under their own power. Most
motile bacteria propel themselves by special
organelles termed flagella. The bacterial flagellum is a
noncontractile, semi-rigid, helical tube composed of
protein and anchors to the bacterial cytoplasmic
membrane and cell well by means of disk-like
structures. The rotation of the inner disk causes the
flagellum to act much like a propeller.
Bacterial motility constitutes unicellular behavior. In
other words, motile bacteria are capable of a behavior
called taxis. Taxis is a motile response to an environmental stimulus and functions to
keep bacteria in an optimum environment. The arrangement of the flagella about the
LabPaq: MBK Page 112
Hands-On Labs, Inc.
bacterium is of use in classification and identification. The following flagellar
arrangements may be found:
1. monotrichous - a single flagellum at......

...Task 5
A. Explain what the methyl red test determines.
Methyl red test is used to determine whether bacteria can perform mixed-acid fermentations when supplied with glucose (Ramakrishnan, & Sulochana, 2012). Methyl red test shows positive when the culture medium turns red after methyl red is added, because of a pH level of 4.4 or below from the fermentation of glucose. On the other hand, methyl red test is negative when the culture medium remains yellow, which occurs when little acid is produced due to the glucose being fermented i.e. high pH level of 6.0 or above.
B. Explain what the Voges-Proskauer test determines.
Voges-Proskauer test is used to identify enteric bacteria based on how they metabolize glucose. The enteric bacteria’s that produce neutral end-products, such as acetoin are detected by VP test (Ramakrishnan, & Sulochana, 2012). Positive test: acetoin + alpha-naphthol + KOH = red color. Negative test: alpha-naphthol +KOH = copper color (Ramakrishnan, & Sulochana, 2012).
C. Discuss which of your organisms, if any, fermented glucose.
S. epidermidis came out positive for glucose fermentation.
D. Discuss which of your organisms, if any, produced measurable acidic by-products.
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E. Explain why organisms...